Evaluation of induction conditions for plasmid pQE-30 stability and 503 antigen of Leishmania i. chagasi expression in E. coli M15.

Evaluation of induction conditions for plasmid pQE-30 stability and 503 antigen of Leishmania i. chagasi expression in E. coli M15.
Appl Microbiol Biotechnol. 2019 Jun 19;:
Authors: Ribeiro VT, Asevedo EA, de Paiva Vasconcelos LTC, Filho MAO, de Araújo JS, de Macedo GR, de Sousa Júnior FC, Dos Santos ES
Abstract
The present study aimed to evaluate the influence of induction conditions (IPTG concentration, temperature, and induction time) on the plasmid pQE-30 stability and 503 antigen expression of Leishmania i. chagasi in Escherichia coli M15. Batch cultures were performed at 37 °C and induced by the addition of different IPTG concentrations (0.01 to 1.5 mM). Subsequently, experiments were carried out at different temperatures (27 to 42 °C), evaluating the influence of induction time (0.5 to 6 h after the start of the culture). The results showed that IPTG toxicity caused a metabolic stress in the cells and, consequently, the microorganism growth reduced. The induction with IPTG may also be associated with the plasmid pQE-30 instability, due to metabolic burden imposed by the recombinant protein expression. The optimal conditions for 503 antigen expression of Leishmania i. chagasi in Escherichia coli M15 were an IPTG concentration of 1.0 mM, temperature of 37 °C, and induction time of 2 h. The maximum antigen concentration obtained was 0.119 ± 0.009 g/L, about seven times higher than the lowest concentration. Therefore, the re...

Source: Applied Microbiology and Biotechnology - June 18, 2019 Category: Microbiology Authors: Ribeiro VT, Asevedo EA, de Paiva Vasconcelos LTC, Filho MAO, de Araújo JS, de Macedo GR, de Sousa Júnior FC, Dos Santos ES Tags: Appl Microbiol Biotechnol Source Type: research